January 31, 2010

Maybe carbon dioxide is not the only factor affecting weather and climate

That’s the thought I had as I read this Wall Street Journal news story headlined, “Slowdown in Warming Linked to Water Vapor.” The lead sentence reads, “Climatologists have puzzled over why global average temperatures have stayed roughly flat in the past decade, despite a long-term warming trend.” The first thought that occurred to me was: Well, maybe it wasn’t an eternal long-term warming trend. We know from history that weather sometimes gets colder and sometimes gets warmer; we have good reason to believe (although Michael Mann’s discredited hockey-stick graph tried to deny this) that temperatures were higher in western Europe and other places in the years from 1000 to 1250 than they have been in the past half-century. And we know that even so London and Paris weren’t under water.

The WSJ story has something like a who’d-a-thunk-it undercurrent. Who’d have thunk that something besides increased carbon dioxide emissions could influence weather and climate? The theory that increased carbon dioxide emissions will increase temperatures is of course absolutely irrefutable if carbon dioxide emissions were the only thing affecting weather and climate. But of course they aren’t. Other such factors include, as the article points out, the concentration of water vapor in the stratosphere, fleeting changes in ocean currents and aberrations in solar activity. Climate scientists don’t seem to fully understand how all these factors and others combine to produce weather and climate. And why should they? Surely the potential interactions are very complex, and probably beyond the capacity of even the most sophisticated computer.

All this points to a common sense conclusion. We should try to understand these things better. But we should not insist that those who doubt the theories—advanced as certainties—by global warming alarmists are like Holocaust deniers. The recent revelations of the Climategate emails and the confession that the prediction that the Himalayan glaciers would melt by 2035 had no scientific basis shows that much of our climate science has been hijacked by those for whom predictions of global warming have taken on the character of a religious faith. Let science be science.